// NumMethods returns the total number of methods of interface t.
// The interface must have been completed.
-func (t *Interface) NumMethods() int { t.assertCompleteness(); return len(t.allMethods) }
-
-func (t *Interface) assertCompleteness() {
- if t.allMethods == nil {
- panic("interface is incomplete")
- }
-}
+func (t *Interface) NumMethods() int { t.Complete(); return len(t.allMethods) }
// Method returns the i'th method of interface t for 0 <= i < t.NumMethods().
// The methods are ordered by their unique Id.
// The interface must have been completed.
-func (t *Interface) Method(i int) *Func { t.assertCompleteness(); return t.allMethods[i] }
+func (t *Interface) Method(i int) *Func { t.Complete(); return t.allMethods[i] }
// Empty reports whether t is the empty interface.
func (t *Interface) Empty() bool {
- if t.allMethods != nil {
- // interface is complete - quick test
- // A non-nil allTypes may still be empty and represents the bottom type.
- return len(t.allMethods) == 0 && t.allTypes == nil
- }
- return !t.iterate(func(t *Interface) bool {
- return len(t.methods) > 0 || t.types != nil
- }, nil)
+ t.Complete()
+ // A non-nil allTypes may still have length 0 but represents the bottom type.
+ return len(t.allMethods) == 0 && t.allTypes == nil
}
// HasTypeList reports whether interface t has a type list, possibly from an embedded type.
func (t *Interface) HasTypeList() bool {
- if t.allMethods != nil {
- // interface is complete - quick test
- return t.allTypes != nil
- }
-
- return t.iterate(func(t *Interface) bool {
- return t.types != nil
- }, nil)
+ t.Complete()
+ return t.allTypes != nil
}
// IsComparable reports whether interface t is or embeds the predeclared interface "comparable".
func (t *Interface) IsComparable() bool {
- if t.allMethods != nil {
- // interface is complete - quick test
- _, m := lookupMethod(t.allMethods, nil, "==")
- return m != nil
- }
-
- return t.iterate(func(t *Interface) bool {
- _, m := lookupMethod(t.methods, nil, "==")
- return m != nil
- }, nil)
+ t.Complete()
+ _, m := lookupMethod(t.allMethods, nil, "==")
+ return m != nil
}
// IsConstraint reports t.HasTypeList() || t.IsComparable().
func (t *Interface) IsConstraint() bool {
- if t.allMethods != nil {
- // interface is complete - quick test
- if t.allTypes != nil {
- return true
- }
- _, m := lookupMethod(t.allMethods, nil, "==")
- return m != nil
- }
-
- return t.iterate(func(t *Interface) bool {
- if t.types != nil {
- return true
- }
- _, m := lookupMethod(t.methods, nil, "==")
- return m != nil
- }, nil)
+ return t.HasTypeList() || t.IsComparable()
}
// iterate calls f with t and then with any embedded interface of t, recursively, until f returns true.
// iterate reports whether any call to f returned true.
+// TODO(gri) This is now only used by infer.go - see if we can eliminate it.
func (t *Interface) iterate(f func(*Interface) bool, seen map[*Interface]bool) bool {
if f(t) {
return true